Abstract:
The pelagic community of the Ross Sea consists of a permanent component (=holoplankton) and a temporary component which is primarily made up from the larval stages of benthic marine invertebrates and fish (= the meroplankton). The distribution and abundance pattern of the meroplankton in the Ross Sea was investigated. A combined morphological and molecular approach was used to identify the ... common larval "types" collected from sites in the Ross Sea along the Victoria Land coast including McMurdo Sound, Granite Harbour, Gerlache Inlet (Terra Nova Bay), and Cape Hallett. Daily samples (where possible) of meroplankton larva were collected in early summer (Nov/Dec) using a 100 micron collapsible plankton net. Plankton samples were sorted fresh, the larvae were quantified and specimens were photographed and preserved for DNA sequence analysis and morphological description. One plankton sample from each site was preserved in a formalin based Steedman's fix and taken to the University of Auckland as a reference samples. A filter bag from the seawater intake to the RO-plant at Scott Base was also analysed. Adult marine invertebrate samples were received from other events sampling efforts and used to form the beginnings of an adult invertebrate database by comparing larval gene sequences with adult sequences. The questions the project specifically addresses are: 1) Is there a latitudinal gradient in meroplankton biodiversity and abundance along the Victoria Land Coast?, and 2) using molecular sequencing, can we quantify the distribution and abundance of common marine invertebrate larvae for a better understanding of the functioning of marine benthic communities in the Ross Sea?